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PostPosted: Wed Aug 26, 2015 9:37 am 
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Joined: Mon Jun 01, 2015 12:59 pm
Posts: 34
Ray Obi-wan and/or other MR Jedi.

Despite adjusting the clutch as per the service manual, she slips badly. Suggestions?


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PostPosted: Wed Aug 26, 2015 1:12 pm 
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Joined: Sun Nov 30, 2008 12:10 pm
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Location: Connecticut, USA
What kind of gearbox oil are you using?

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Wed Aug 26, 2015 3:11 pm 
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Joined: Mon Jun 01, 2015 12:59 pm
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Shell Rotella 15-40, dino oil. Same as I use in my V-Strom, GasGas trials bike, PE400, TC100 and BSA 441. Beginning to wonder if it's time for a new clutch and springs. Clutch is adjusted per manual spec. Approximately 1/8" free-play at the clutch lever end. Starts out strong, shift up to 3rd or open the throttle and you can feel it slipping, as in more throttle does not equal more speed. I can feel the slipping up through all gears.


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PostPosted: Wed Aug 26, 2015 3:48 pm 
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Joined: Sun Nov 30, 2008 12:10 pm
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Location: Connecticut, USA
Yes, that sounds quite familiar.

My first clutch rebuild (in 2008) used all new OEM plates & springs, and Mobil One synthetic oil. That clutch slipped from the moment I put it in gear (which is why I asked about the oil). I re-used the springs & steel plates (fibers were ruined) with another new set of OEM frictions & Spectra 10W-40 dino oil, which lasted about one full season of riding before starting to slip in the higher gears. After that I rebuilt using all Barnett parts (slight slippage after a month or so), then rebuilt again w/all OEM plates & Barnett 501-29-06072 springs; this clutch still works perfectly over 6,000 hard miles later, on a heavily modified motor. I'm going to replace it now whether it needs it or not. :)

It would surely be best to rebuild your clutch completely using OEM plates & Barnett springs, but another option would be to sand all plates lightly w/400 grit paper and re-use them with new Barnett springs. If you decide to replace w/OEM plates and can't find them let me know, there are some later Honda plates that should work fine. Also, the clutch hub splines and basket 'fingers' should be filed flat if they show any notching (which they usually do), otherwise the clutch won't engage/disengage smoothly.

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Thu Aug 27, 2015 8:00 am 
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Joined: Mon Jun 01, 2015 12:59 pm
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Thanks Ray. I have a set of NOS OEM plates to try and some replacement springs. What are the other plates which will work?
IJ


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PostPosted: Thu Aug 27, 2015 8:55 am 
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Location: Connecticut, USA
The 22201-GBF-B40 friction plates fit fine and are the same .106" thickness as the OEM MR plates, and the 22201-GF6-000 frictions are .010" thicker than OEM. The MT125 steel plates 22321-KE8-000 / 22321-361-000 are .012" thicker than OEM (the MT clutch uses one less friction & steel plate), I think they would work; the clutch pack would be @1.5mm wider than stock.

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Thu Aug 27, 2015 9:39 am 
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Thanks Ray
IJ


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PostPosted: Fri Aug 28, 2015 11:03 am 
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Joined: Fri Jul 14, 2006 8:12 am
Posts: 323
Location: Wuppertal/Germany
you both should better use a motorcycle oil that is made for clutch and transmission work.
as a very good alternative you can fill in ATF Dex II.

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